As a conventional vibration isolator of this type a structure is known in which there are provided: a cylindrical first mounting component which is connected to either a vibration generating portion or a vibration receiving portion; a second mounting component which is connected to the other one of the vibration generating portion and the vibration receiving portion; a rubber elastic body which elastically connects together these two mounted components and closes off an aperture portion on one side in the axial direction of the first mounting component; a diaphragm which closes off an aperture portion on the other side in the axial direction of the first mounting component; and a partitioning component which partitions the interior of the first mounting component into a primary liquid chamber in which the rubber elastic body forms a portion of the partition wall, and a secondary liquid chamber in which the diaphragm forms a portion of the partition wall, wherein an orifice passage which enables the primary liquid chamber to communicate with the secondary liquid chamber is formed between an outer circumferential surface side of the partitioning component and an inner circumferential surface side of the first mounting component.
In recent years, as is shown, for example, in Patent document 1 (see below), a vibration isolator has been proposed in which a liquid mixture which contains a plurality of types of liquid is sealed inside the first mounting component.
The following method may be considered as the method used to manufacture this type of vibration isolator. Firstly, a main body rubber component in which the first mounting component and the second mounting component are connected together by means of the rubber elastic body is formed. Next, the partitioning component and the diaphragm are fitted to this main body rubber component, and the interior of the first mounting component is partitioned into the primary liquid chamber and the secondary liquid chamber and is tightly sealed. Air is then expelled from the interior of the first mounting component so as to place it under negative pressure, and the liquid mixture is injected into the interior of the first mounting component by the suction force created by this negative pressure thereby forming a vibration isolator.